A 12-year-old Bolivian boy has been hailed as the world's youngest professional footballer after making his debut in a first division match in La Paz.

Mauricio Baldivieso came on for the final nine minutes in a game between La Paz FC and Aurora, where his father is coach. Aurora were losing 1-0 and a hefty tackle left the youth bruised and briefly close to tears but he ended the match on Sunday as a celebrity. "I am the happiest man in the world," he said.

He beat South America's previous youngest professional, Fernando García, who made his debut in Peru in 2001 aged 13. According to Fifa records, Souleymane Mamam of Togo became the youngest player to take part in a World Cup qualifying match in 2001, at the age of 13. He may have played professionally when he was 12 but there are no records.

Baldivieso's passion for the game is not in question but with his father, Julio César Baldivieso, as Aurora's player-coach, accusations of nepotism tinged the precocious debut. "I am very proud, he's got a lot of talent," said the coach. Father and son share the same shirt number, 10.

The former international, who played in the 1994 World Cup, hopes Bolivia will produce global stars. "Why does it always have to be players from Argentina or Brazil? Why always a Maradona or Kaka? Why can't they be players from Bolivia?"

He had originally hoped to introduce Mauricio when Aurora were leading but sent him in when the team were a goal down to La Paz FC. A defender showed the debutant no mercy and brought him down with a foul. The 12-year-old was distraught and had to be treated by medics but returned to the fray for the final four minutes, earning a standing ovation.

Some doctors said pitting Mauricio against adults exposed him to potentially permanent injury because his bones were not yet fully grown. "This is compromising his sporting future for life," Raúl Alberto Morales, a medic for another club, said.

Julio César Baldivieso said his son did karate and could handle the demands of professional football. The debut was not a stunt, he said, adding that he would turn out this year to play alongside his son.